html,
        body {
            padding: 0;
            margin: 0;
            width: 100%;
            height: 100%;
            overflow: hidden;
        }

        .top {
            z-index: 9999999;
            position: absolute;
            top: 0;
            left: 0;
            height: 50px;
            line-height: 50px;
            width: 100%;
            background: #FFFFFF;
            border-bottom: 3px solid #dedede;
        }

        .signature-title {
            height: 50px;
            line-height: 60px;
            display: inline-block;
            width: 90%;
            margin-left: 10px;
            text-align: left;
            font-size: 20px;
            font-weight: bold;
            color: #6aa8e7;
        }

        .clear_canvas {
            position: absolute;
            right: 325px;
            top: 0;
            font-size: 18px;
            background: #FF0000;
            color: #fff;
            padding: 0 20px;
            border-radius: 4px;
            height: 35px;
            line-height: 35px;
            margin-top: 9px;
        }

        .undo_canvas {
            position: absolute;
            right: 230px;
            top: 0;
            font-size: 18px;
            background: #ff7300;
            color: #fff;
            padding: 0 20px;
            border-radius: 4px;
            height: 35px;
            line-height: 35px;
            margin-top: 9px;
        }

        .redo_canvas {
            position: absolute;
            right: 135px;
            top: 0;
            font-size: 18px;
            background: #00aeff;
            color: #fff;
            padding: 0 20px;
            border-radius: 4px;
            height: 35px;
            line-height: 35px;
            margin-top: 9px;
        }

        .sure_canvas {
            position: absolute;
            right: 10px;
            top: 0;
            padding: 0 20px;
            background: #20A53A;
            border-radius: 4px;
            color: #fff;
            height: 35px;
            line-height: 35px;
            margin-top: 9px;
        }